Adrenergic Pharmacology Flashcards

1
Q

What catalyzes the conversion of l-DOPA to Dopamine?

A. Tyrosine hydroxylase

B. DOPA decarboxylase (AAADC)

C. Dopamine B-hydroxylase

D. Phenylethanolamine N-methyltransferase

A

B - aromatic l-amino acid decarboxylase (AAADC) catalyzes conversion

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2
Q

What inhibits the synthesis of l-DOPA to dopamine?

A. Carbidopa

B. tyrosine hydroxylase

C. a-methyltyrosine

D. a-methyldopa

A

A

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3
Q

______________ is used for pre-operative reduction of catecholamine synthesis in pheochromocytoma, a neuroendocrine tumor of the medulla.

A. Carbidopa

B. tyrosine hydroxylase

C. a-methyltyrosine

D. a-methyldopa

A

C - a-methyl tyrosine is a synthetic analog of tyrosine that inhibits tyrosine hydroxylase

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4
Q

_______ is a synthetic analog of tyrosine that inhibits tyrosine hydroxylase.

A. Carbidopa

B. DOPA decarboxylase

C. a-methyltyrosine

D. a-methyldopa

A

C

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5
Q

During autoregulation of neurotransmission, stimulation of ______________ adrenergic receptors inhibits norepinephrine release.

A. pre-synaptic a2

B. post-synaptic a2

C. pre-synaptic a1

D. pre-synaptic B2

E. post-synaptic B2

A

A

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6
Q

During autoregulation of neurotransmission, stimulation of ______________ adrenergic receptors potentiates norepinephrine release.

A. pre-synaptic a2

B. post-synaptic a2

C. pre-synaptic a1

D. pre-synaptic B2

E. post-synaptic B2

A

D

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7
Q

If a large amount of norepinephrine is released into the bloodstream, NE may act on distant effect cells. NE spillover is __________ in congestive heart failure.

A. increases

B. unchanged

C. decreases

A

A

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8
Q

What two types of drugs inhibit neuronal uptake of norepinephrine?

A
  1. Cocaine
  2. Tricyclic antidepressants
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9
Q

Active transport of norepinephrine through th emembrane by other tissues/organs/transporters is inhibited by ____________.

A

steroid hormones/corticosterone

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10
Q

The major metabolite from the final metabolic disposition of catecholamines is ____________.

A

vanillylmandelic acid

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11
Q

a-Methyldopa is a ___________ that functions as an anti-hypertensive.

A. presynaptic a1 agonist

B. presynaptic a2 agonist

C. postsynaptic a1 agonist

D. presynpatic a1 antagonist

E. postsynaptic a2 antagonist

A

B - a2 reduces central sympathetic outflow as an a2 agonist “false neurotransmitter”

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12
Q

Which functions to deplete NE from adrenergic terminals via inhibition of transporter systems of storage vesicles?

A. Bretilium

B. Guanethidine

C. Reserpine

D. Cocaine

E. a-methyldopa

A

C - resepine promots depletion and destruction of NE.

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13
Q

Which causes accumulation of NE at the receptor site due to inhibition of NE re-uptake?

A. Cocaine

B. TCAs

C. Bretilium

D. Guanethidine

E. A and B

F. C and D

A

E

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14
Q

Which drugs function to replace NE in vesicles and prevent norepinephrine release from storage vesicles?

A. Cocaine

B. TCAs

C. Bretilium

D. Guanethidine

E. A and B

F. C and D

A

F

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15
Q

a2 post-synaptic adrenergic receptors are located elsewhere on the vascular muscle cells and activated mainly by circulating catecholamines, but predominantly __________.

A. Epinephrine

B. Norepinephrine

C. Dopamine

D. None of these

A

A

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16
Q

__________ receptors are located close to the site of NE release and are mainly responsible for neuronal NE mediated vasoconstriction of smooth muscle.

A. a1 presynaptic

B. a1 postsynaptic

C. a2 presynaptic

D. a2 postsynaptic

A

B

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17
Q

Vasoconstriction in the skin and splanchnic vascular beds (and large arteries/veins) is mediated by ______________ adrenergic receptor stimulation.

A. a1 presynaptic

B. a1 postsynaptic

C. a2 presynaptic

D. a2 postsynaptic

A

B

18
Q

Activation of ____________ receptors in the vasomotor center has a sympathoinhibitory effect to reduce central sympathetic outflow and vasomotor tone (i.e. reduced blood pressure and heart rate, reduced renin release).

A. a1 presynaptic

B. a1 postsynaptic

C. a2 presynaptic

D. a2 postsynaptic

A

C

19
Q

Activation of ______________ adrenergic receptors in the sympathetic nerve endings inhibits norepinephrine release.

A. a1 presynaptic

B. a1 postsynaptic

C. a2 presynaptic

D. a2 postsynaptic

A

C

20
Q

Stimulation of ___________ adrenergic receptors in the kidney induces renin release.

A. a1

B. a2

C. B1

D. B2

A

C

21
Q

Stimulation of ________________ adrenergic receptors causes relaxation of most types of smooth muscle.

A. B1 presynaptic

B. B2 presynpatic

C. B1 postsynaptic

D. B2 postsynaptic

A

D

22
Q

Stimulation of ___________ receptors increases NE release from sympathetic nerve endings.

A. B1 presynaptic

B. B2 presynpatic

C. B1 postsynaptic

D. B2 postsynaptic

A

B

23
Q

Which receptors stimulate insulin secretion in the pancreas and thereby increase glucose uptake in skeletal muscles?

A. B1 presynaptic

B. B2 presynpatic

C. B1 postsynaptic

D. B2 postsynaptic

A

D

24
Q

The B1 adrenergic receptor causes:

A. relaxation of bronchial smooth muscle

B. increases in glycogenolysis in skeletal muscle

C. contraction of radial muscle in the eye

D. increases in renin release in the kidney

A

D

25
Q

The B2 adrenergic receptor causes:

A. relaxation of bronchial smooth muscle

B. decreases in glycogenolysis in skeletal muscle

C. contraction of radial muscle in the eye

D. increases in renin release in the kidney

A

A

26
Q

The a1 adrenergic receptor causes:

A. relaxation of bronchial smooth muscle

B. increases in glycogenolysis in skeletal muscle

C. contraction of radial muscle in the eye

D. increases in renin release in the kidney

A

C

27
Q

Norepinephrine has the highest affinity for which receptor?

A

B1 (>a1>a2)

28
Q

____________ is a drug of choice for anaphylactic shock.

A

Epinephrine

29
Q

At high doses, dopamine activates the a1 receptor and has the following effect:

A. Decreases renal and splanchnic blood flow

B. Increases cardiac contractility

C. Increases splanchnic and renal blood flow

D. Increases cerebral and coronary blood flow

A

A - marked tachycardia may occur with high doses of DA

30
Q

Uncontrolled hypertension that is paroxysmal in nature (during adrenergic crisis) is indicative of ____________.

A

Pheochromocytoma (shown by VMA levels in the urine)

31
Q

A mid-level dose of dopamine will have the following effect:

A. activation of B1 receptor

B. increases cardiac contractility

C. no effect on BP/HR

D. All of the above result from mid-level DA doses

A

D

32
Q

In heart failure, responsiveness to B-adrenergic stimulation in suppressed, mainly because of ___________.

A

downregulation of the B1-adrenergic receptor

33
Q

Ephedrine is classified as:

A. non-selective direct-acting sympathomimetic

B. selective direct-acting sympathomimetic

C. indirect-acting sympathomimetic

D. mixed-acting sympathomimetic

A

D

34
Q

Which two drugs are adrenergic agonists that are not sympathomimetics?

A

Clonidine and a-methyl DOPA are adrenergic agonists that have sympathoinhibitory effects

35
Q

MAO and COMT inhibitors are ________ drugs.

A. non-selective direct-acting sympathomimetic

B. selective direct-acting sympathomimetic

C. indirect-acting sympathomimetic

D. mixed-acting sympathomimetic

A

C

36
Q

________________ act pre-synaptically to increase catecholamine availability.

A. non-selective direct-acting sympathomimetic drugs

B. selective direct-acting sympathomimetic drugs

C. indirect-acting sympathomimetic drugs

D. mixed-acting sympathomimetic drugs

A

C

37
Q

___________ release norepinephrine and act directly on adrenergic receptors.

A. non-selective direct-acting sympathomimetic drugs

B. selective direct-acting sympathomimetic drugs

C. indirect-acting sympathomimetic drugs

D. mixed-acting sympathomimetic drugs

A

D

38
Q

Central sympatholytic drugs are also known as agonists of what receptor?

A

presynaptic a-2 agonists

39
Q

Why should beta blockers be used cautiously in diabetics?

A

They can mask the tachycardia that serves as a warning sign for insulin induced hypoglycemia.

40
Q

Which drug is NOT an inhibitor of adrenergic nerve terminals?

A. Reserpine

B. Guanethidine

C. Clonidine

D. Guanabenz

A

C - Clonidine and a-methyldopa (not listed) are sympatholytic drugs taht stimulate central a2 adrenergic receptors in the medulla.